MASS DRINKING WATER
DISTRIBUTION GRADE 1 LATEST
STUDY GUIDE 70 + QUESTIONS
AND CORRECT ANSWERS
2025/2026 .
1/8
, 1. After a new water mains is installed and pressure tested it should be✔✔ correct answer Filled with a solution of 25ppm to
50ppm free chlorine for at least 24 hours prior to flushing
2. as the temperature of water increases the disinfection process✔✔ correct answer more ettective
3. water with a ph of 8.0 is considered✔✔ correct answer basic
4. what is a low voltage electrical system that is used to prevent rust corrosion and pitting of metal surfaces in contact
with water✔✔ correct answer cathodic protection
5. Which conventional treatment step is eliminated by direct filtration✔✔ correct answer Sedimentation
6. A granular white powder used for disinfection✔✔ correct answer Calcium hypochlorite
7. What is the chlorine dose✔✔ correct answer Chlorine demand plus chlorine residual
8. what is a cross connection✔✔ correct answer an unprotected connection between a drinking water supply and a system not approved as safe
9. what is an air gap separation device✔✔ correct answer a vertical empty space that seperates a drinking water suppy from an unapproved water system
10. breakpoint chlorination is the addition of chlorine into the water until what occurs✔✔ correct answer the chlorine
demand has been satisfied
11. what is the main difference between using hypochlorite compounds and chlorine gas✔✔ correct answer the % of
available chlorine
12. what is disenfection✔✔ correct answer process that kills or inactivates most microorganism and pathogens
13. why is backflow a concern for water distribution systems✔✔ correct answer flow from a non potable water source could
contaminate the water system
14. which of the following has caused more waterborne disease outbreaks than any other reported factor✔✔ correct
answer cross connection contamination
15. what contaminant causes methemoglobinemia✔✔ correct answer nitrate
2/8
DISTRIBUTION GRADE 1 LATEST
STUDY GUIDE 70 + QUESTIONS
AND CORRECT ANSWERS
2025/2026 .
1/8
, 1. After a new water mains is installed and pressure tested it should be✔✔ correct answer Filled with a solution of 25ppm to
50ppm free chlorine for at least 24 hours prior to flushing
2. as the temperature of water increases the disinfection process✔✔ correct answer more ettective
3. water with a ph of 8.0 is considered✔✔ correct answer basic
4. what is a low voltage electrical system that is used to prevent rust corrosion and pitting of metal surfaces in contact
with water✔✔ correct answer cathodic protection
5. Which conventional treatment step is eliminated by direct filtration✔✔ correct answer Sedimentation
6. A granular white powder used for disinfection✔✔ correct answer Calcium hypochlorite
7. What is the chlorine dose✔✔ correct answer Chlorine demand plus chlorine residual
8. what is a cross connection✔✔ correct answer an unprotected connection between a drinking water supply and a system not approved as safe
9. what is an air gap separation device✔✔ correct answer a vertical empty space that seperates a drinking water suppy from an unapproved water system
10. breakpoint chlorination is the addition of chlorine into the water until what occurs✔✔ correct answer the chlorine
demand has been satisfied
11. what is the main difference between using hypochlorite compounds and chlorine gas✔✔ correct answer the % of
available chlorine
12. what is disenfection✔✔ correct answer process that kills or inactivates most microorganism and pathogens
13. why is backflow a concern for water distribution systems✔✔ correct answer flow from a non potable water source could
contaminate the water system
14. which of the following has caused more waterborne disease outbreaks than any other reported factor✔✔ correct
answer cross connection contamination
15. what contaminant causes methemoglobinemia✔✔ correct answer nitrate
2/8
